Never understood the cry for more gun laws since the government seems wholly uninterested in enforcing the ones on the books now.
I do not know how all the nuclear weapons were "lost", however, most of them were nuclear events. They weren't just misplaced or left in a bathroom somewhere. For example an aircraft has a problem and makes an emergency landing with a nuclear weapon. Those are called "Broken Arrows". We used to have frequent Broken Arrow exercises while in the Air Force. I agree that the US government should not be trying to take AR-15s, but this is not the right logic.
Here is a list. They even included an incident by the Russians. https://www.businessinsider.com/list-of-broken-arrow-nuclear-accidents-2013-5